Endomyocardial fibrosis and eosinophilia.
Absolute eosinophil counts were assessed in 15 African patients with proven endomyocardial fibrosis. Though the mean eosinophil count in patients with endomyocardial fibrosis was higher compared with the normals reported from Kampala (1-13 vs 0.72X10(9)/1), the absolute range was comparable. A high percentage of patients with endomyocardial fibrosis had malarial parasites, high malarial antibody titres, hookworms, or strongyloides, but the correlation of eosinophilia to various parasitic infections was poor. Both eosinophilia and parasitic infections are common in the tropics and they effect patients with endomyocardial fibrosis no more than the population at large. Other aetiological factors, genetic, environmental, and immunological, are felt to be important in the causation of endomyocardial fibrosis in Uganda and evidence for this is reviewed. Though there is a similarity in pathological features, African endomyocardial fibrosis is a distinct entity from Löffler's endocarditis and cardiac lesions seen in eosinophilic leukaemia or reactive eosinophilia. There is no hard evidence to suggest that African endomyocardial fibrosis is a variant of Löffler's endocarditis caused by parasitic infections via eosinophilia.